Life histories of North American woodpeckersBent, Arthur Cleveland
Science
Life histories of North American woodpeckers
Bent, Arthur Cleveland
Birds -- North America; Woodpeckers -- North America
Beetles taken collectively amount to 21.55 percent, and are
the largest item of the food. Of these, a little less than
14 percent are wood-boring larvae. * * * They were found in
289 stomachs, or about 40 percent of all, and 10 contained
no other food. This is only about half the amount found in
the stomachs of the hairy woodpecker, and shows that the
downy pecks wood much less than the hairy. These larvae
are eaten at all times of the year, though the most are
taken in the cooler months. * * * The economic value of the
destruction of these larvae is very great.
Weevils amount to a little more than 3 percent, but appear
to be a rather favorite food, as they were found in 107
stomachs. * * *
Ants are eaten by the downy to the extent of 21.36 percent
of its diet, and are taken more regularly than any other
element of the food. * * *
Caterpillars appear to be a very acceptable food for the
downy woodpecker, as they constitute 16.50 percent of the
yearly diet. * * *
Fruit was eaten to the extent of 5.85 percent of the whole
food. Most of it is of useless wild varieties. * * *
The charge sometimes made that the downy injures trees by
eating the inner bark is disproved. It eats cambium rarely
and in small quantities.
Beal gives a list of 20 seeds and fruits found in the downy’s food.
Summarizing his findings, he says: “The foregoing discussion of the
food of the downy woodpecker shows it to be one of our most useful
species. The only complaint against the bird is on the score of
disseminating the poisonous species of Rhus. However, it is fortunate
that the bird can live on this food when it is difficult to procure
anything else. The insect food selected by the downy is almost all of
species economically harmful.”
Forbush (1927) lays stress on the usefulness of the downy to man; he
says that it “searches out the pine weevil which kills the topmost
shoot of the young white pine and so causes a crook in the trunk of the
tree, unfitting it for the lumber market.”
Mrs. Alice Hall Walter (1912) shows how well the downy is equipped to
secure its food. She says that the feet, two toes in front and two
behind, “serve to _clamp_ the bird to the tree.” She continues:
Additional support is furnished by the stiff, sharply
pointed tail-feathers, that act as a brace when the bird
delivers heavy blows with its beak. Effective as this
tool is for the work of _hammer_, _wedge_, _drill_ and
_pick-axe_, it could not obtain the deeply hidden grubs
known as “borers,” from their tortuous, tunneled grooves,
without the aid of the long, slender, extensile tongue. In
the case of the Hairy and Downy, as well as some others of
the family, this remarkable tool is provided with barbs,
converting it into a spear, which may be hurled one inch,
two inches or even more, beyond the tip of the beak.
Public-domain text, read in full here on John Shaqi.
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